• CVE-2023-52733

发布时间: 2024年5月31日

修改时间: 2025年4月13日

概要

In the Linux kernel, the following vulnerability has been resolved: s390/decompressor: specify __decompress() buf len to avoid overflow Historically calls to __decompress() didn't specify "out_len" parameter on many architectures including s390, expecting that no writes beyond uncompressed kernel image are performed. This has changed since commit 2aa14b1ab2c4 ("zstd: import usptream v1.5.2") which includes zstd library commit 6a7ede3dfccb ("Reduce size of dctx by reutilizing dst buffer (#2751)"). Now zstd decompression code might store literal buffer in the unwritten portion of the destination buffer. Since "out_len" is not set, it is considered to be unlimited and hence free to use for optimization needs. On s390 this might corrupt initrd or ipl report which are often placed right after the decompressor buffer. Luckily the size of uncompressed kernel image is already known to the decompressor, so to avoid the problem simply specify it in the "out_len" parameter.

CVSS v3 指标

NVD openEuler
Confidentiality
Attack Vector
CVSS评分 N/A N/A
Attack Complexity
Privileges Required
Scope
Integrity
User Interaction
Availability

安全公告

公告名 概要 发布时间
KylinSec-SA-2024-2509 In the Linux kernel, the following vulnerability has been resolved: s390/decompressor: specify __decompress() buf len to avoid overflow Historically calls to __decompress() didn't specify "out_len" parameter on many architectures including s390, expecting that no writes beyond uncompressed kernel image are performed. This has changed since commit 2aa14b1ab2c4 ("zstd: import usptream v1.5.2") which includes zstd library commit 6a7ede3dfccb ("Reduce size of dctx by reutilizing dst buffer (#2751)"). Now zstd decompression code might store literal buffer in the unwritten portion of the destination buffer. Since "out_len" is not set, it is considered to be unlimited and hence free to use for optimization needs. On s390 this might corrupt initrd or ipl report which are often placed right after the decompressor buffer. Luckily the size of uncompressed kernel image is already known to the decompressor, so to avoid the problem simply specify it in the "out_len" parameter. 2024年5月31日

影响产品

产品 状态
KY3.4-4A kernel Unaffected
KY3.4-5A kernel Unaffected
KY3.5.1 kernel Unaffected
KY3.5.2 kernel Unaffected
KY3.5.3 kernel Unaffected
V6 kernel Unaffected